The present invention generally relates to a drug dispensing apparatus and more particularly, to an automatically controlled drug dispensing apparatus having a drug dispensing cartridges storing unit, a drug doses packing unit and a control means, capable of dispensing an individual drug dose or doses to a common collection area from one or more drug dispensing cartridges for packaging purpose thereof.
In the drug dispensing apparatus according to the present invention, a plurality of drug dispensing cartridges are removably disposed side by side and vertically in the drug dispensing cartridges storing unit. A drug dose or doses from one or more drug dispensing cartridges properly selected in accordance with input information which is given through the control means, are collectively packaged in the drug doses packing unit. The drug dispensing unit is composed of both of the drug dispensing cartridges storing unit and the drug doses packing unit of the apparatus.
The present invention intends to provide designs of the cartridge storing the drug doses in tablet or capsule form or the like, arrangements thereof in the drug dispensing unit, constructions of the unit or the like.
With regard to the drug dispensing cartridges, a couple of prior arrangements are disclosed in Japanese Utility Model Publications (Jikkosho) No. 52-34786 and No. 56-44728.
In the case of the former arrangement, each individual drug dose can be taken out from the cartridge in such a manner that a tube for arraying the drug doses is pushed up in a drug storing portion by means of a solenoid so as to accommodate the individual drug doses therein. Since the drug doses stored in the storing portion are stirred through the push-up motion of the tube as described above, they can be steadily taken out from the cartridge. The disadvantage of this kind of means is that a large noise tends to be made with the push-up motion.
The latter arrangement contains a wheel for arraying the drug doses, whereon are arranged a plurality of grooves. The drug doses are caught on the grooves are taken out therefrom by spontaneous falling due to gravity, while the wheel is being rotated. The disadvantage of this kind of means is in its low speed for removing the drug doses using gravity, in spite of the advantage of having low noise in its operating condition, since the drug doses are taken out from the grooves by the rotation of said wheel.
In addition, a disadvantage in each of the prior art arrangements as described above resulted from the spontaneous falling of the drug doses, when they are in series at an outlet since some of them will simultaneously be discharged from the dispenser.
Furthermore, in the foregoing arrangements, the only means to detect the drug doses discharged is a direct detection thereof. A photoswitch generally adopted for this purpose sometimes misses the detection of the drug doses, although this kind of trouble depends upon a passing condition thereof. Also, the detecting ability of the photoswitch decreases when the drug doses are powdery and attaches thereon.
Accordingly, although it is desirable to obtain a drug dispensing cartridge capable of dispensing the drug doses one at a time by a means other than that of spontaneous falling to discharge the individual drug doses separately out of a drug outlet, the disadvantages of a cartridge is that it requires a long time to supply the drug doses. Moreover, when the cartridge is overloaded such as clogging of the drug dose in the taking out or discharging process thereof, the drug dose or the cartridge is undesirably damaged.
The cartridge storing unit of a prior apparatus according to another prior art arrangement, is disclosed in Japanese Utility Model Publication (Jikkosho) No. 54-22551. A plurality of drug dispensing cartridges are accommodated in the storing unit having a construction like shelves and placed thereon in a manner that the drug outlet on each drug dispensing cartridge is coincidentally arranged on each opening provided on one of the shelves for discharging the drug doses. The cartridge is electrically connected with the apparatus through a connector provided on a rear plate of the shelves.
In the case as described above, a falling passage for the drug doses discharged out of the cartridges cannot be formed behind the rear plate due to the wires that provide signals to the cartridges.
Consequently, as disclosed in Japanese Utility Model Publication (Jikkosho) No. 54-22551, it is necessary to form the falling passage under the bottom plates of the shelves. Where each cartridge is placed one upon another vertically, a stair-step-like construction of the shelves results. However, this construction is a drawback due to the large size of the drug dispensing unit of the apparatus.
In addition, Japanese Utility Model Publication (Jikkosho) No. 54-10239 discloses a drug dispensing cartridge having a guide portion and an engaging piece for an engagement thereof with one of the shelves, whereby each cartridge can be properly placed in the apparatus.
A position where a certain cartridge is placed is generally determined in conjunction with the kind of drug doses stored in the cartridge. A discharging signal is sent to the cartridge corresponding to a desired position when the drug dose or doses are discharged. The cartridge must be, therefore, properly replaced where it was, when it is taken from the apparatus for replenishment of the drug doses or the like.
Since an essential object of the above prior art is to provide a reliable electrical connection between the drug dispensing cartridge and the apparatus, even if a cartridge storing a different kind of drug doses is placed in a certain position of the apparatus, a merely correct displacement of the cartridge results in a completed electrical connection between the cartridge and the apparatus. Consequently, a mistake can arise in discharging the wrong kind of drug doses since the cartridge can be stored at any position in the apparatus.
Furthermore, Japanese Utility Model Publication (Jikkosho) No. 57-2241 discloses the drug dispensing apparatus having a construction wherein individual drug doses dispensed from each drug dispensing cartridge are led to a common falling passage. However, the above construction causes "cross contamination". That is, a collision of the drug doses dispensed from the cartridges against any of the side walls of the falling passage brings about drug powder adherent to the side walls. This results in undesirable adherence thereof to other drug doses and this is particularly undesirable for pure drug doses.
According to Japanese Utility Model Publication (Jikkosho) No. 57-2241 as mentioned above, therefore, the falling passage is easily cleaned and inspected due to the construction of the falling passage being freely opened and closed. Nevertheless, it is still difficult to clean the inner part of the falling passage in the case of a long passage of a large-sized drug dispensing unit.